Long-stroke pumping jack



April 29, 1930. J, 5 HUNTER 1,756,089

LONG STROKE PUMPING JACK Filed Oct. 26, 1929 2 Sheets-Sheet 1 April 29,1930. 1 s HUNTER 1,756,089

LONG STROKE PUMPING JACK Filed Oct. 26, 1929 2 Sheets-Sheet 2 go If; (o(o (o '(0 wy/m Patented Apr. 29, 1 930 JOHN S. HUNTER, OF GOALINGA,CALIFORNIAl LONGSTROKE PUMPING JACK Application led October 26, 1929.Serial No. l402,606.

This invention relates to a device for trans-. mitting rotary motion toreciprocating motion, and further relates to a device of this characterwhich may be used as a long stroke pumping jack for reciprocating thepump rods ofa deep well pump.

In oil wells reciprocating pumps are often placed at great depths, withthe result that the elongation and contraction of the pump rods of thepump play a very important part in the 'efficiency of the pumping'equipment. It is found that to increase the length' of stroke of a pumpof the type used in pumping oil from wells will reduce the lossesresulting in change of length of the pump rods or sucker rods as suchparts are reciprocated.

Itis an object of my invention to provide a device which willeconomically and efficiently transfer rotary motion to a longreciprocating motion, it being possible tto make the length of thereciprocating stroke of any desired magnitude by merely changing thelength of traveler members or chains and repositioning the guide membersor sprockets over which these chains travel. .s

A further object of the invention is to provide a simple form of bracketmeans for connecting the traveler members or chains to a reciprocatingmember such as a string of sucker rods.

A furthergobject of the invention is to provide a simple means forpreventing bending or disaligning of .the upper end of the polish rod ofa string of sucker rods.

Further objects and advantages of the invention will be made evidentthroughout the following part of the specification. Referring to thedrawings which are'for illustrative purposes only,"

Fig. l'is a front elevational view showing a device embodyingthe'present invention.

2 visa side elevation corresponding to Fig. 3 isa horizontal crosssection on'a plane represented by theline 3-3 of Fig. 2,

Fig.'4 is a diagrammatic viewv for demoni' strating the operationof'thealignment com- I Avpensating device formingfpart ofthe invention.

5 is an enlarged partlyy sectioned de'- tail showing an alternative formof alignment compensating device.

In the embodiment of my invention represented in the drawings I show aframe 11 consisting of vertical posts 12 and 13 which extend upwardlyfrom a base structure 14 and have their upper ends connected together bya cross bar 15. The base member 14 is adapted for mounting on the floor16 of a derrick in such position that the posts 12 and 13 will be spacedon either side of a pump tubing 17 which projects upwardly from a wellcasing 18 and through the floor 16 of the derrick,

project forwardly from the posts 12 and 13, 7 shafts 26 and 27 are heldin inwardly projecting positions of axial alignment, as shown in Figs. 1and 3, and on the inner ends of these shafts 26 and 27 upper sprockets28 and 29 are mounted. By means of lower brackets 32 and-33, lowershafts 34 and 35 are held in inwardly extended and axially alignedposi-v tion. it being preferable to place the lower shafts 34 and 35 ina vertical plane extending through the upper shafts 26 and 27. Moilntedon the inner ends of the shafts 34 and 35 are lower sprockets 36 and 37which are vertically aligned with the respective upper sprockets 28 and29. Over the righthand vertically aligned sprockets 28 and 36 a travelermember or chain 40 is carried, and over the left-hand pair of sprockets29 and 437 From Fig.- 2 it will be noted that the axes a traveler.member or chain 41 is carried.

polish rod 20 all yextend in the same vertical I plane, and it vwill befurther noted that the front and back, vertical portions 42 and 43 ofthe chain loops 40, and 41 extend parallel to and equi-distant from thevertical `plane defined by the axes of the sprockets 28 and 29, and 36and 37.

Secured to the chains 40 and 41 is a bracket member consisting ofright-hand and lefthand up er bracket bars 46 and right-hand and leftandlower bracket bars 47. flhe upper bracket bars 46 have bridge .portions48 which extend externally over the chains 40 and 41 so that the bracketbars 46 may be secured to the chains 40 and 41 by means of pins 49, andthe lower bracket bars 47 likewise have bridge portions 50 extendingexternally over the chains 40 and 41 so that the vbracket bars 47 may besecured to the chains 40 and 41 by vuse of pins 51. The upper bridges 48and the lower bridges 5() are spaced apart on the chains 40 and 41, :andthe bracket bars 47 extend convergently to v engagement with ahorizontally directed pin 20or bolt 53, this pin or bolt 53 extendingthrough the overlappinv extended ends of the bracket bars 46 and 47,through the lower ends of vertical hanger 'straps 54, and through acentral roller which serves as a slide member within a slide or loop 56in a sucker rod clamp member 57 which may 'be secured to the upper endof the polish rod 20. As shown in Fig. 2, the chains 40 and 41 Iwhichconstitute traveler members are each guided by the respective upper andlower sprockets so as to form` flattened vertical loops having sideportions 42 and 43 and having substantially semi-circular end portionswhere the chains extend over the upper and lower sprockets. The bracket45 extends inwardly relative to the fiat loop formed by the chain 40 alldistance substantially equal to half the width of the loop, or in`other words, half the distance between the vertical vportions 42 and 43of the loop. From Fig. 2 it will be perceived that as the chains 40 and41 move in a direction indicated by the arrow 58, the bracket 45 will becarried vertically downwardly, and the bolt 53 at the innerend ofthebracket will travel through the vertical plane defined by the axes ofthe upper and lower sprockets 28 and 29, 36 and 3 Duringthis verticalmovement of the reciprocating parts, the roller 55 willl restsubstantially centrall within the laterally flattened loop 56, as s ownin Figs. 2 and 4. When the bracket 45 reaches and -is carried around thelower sprockets '36 and 37, the roller 55 will be laterally offset for ashort period of time, which will cause the roller to move laterally-intoan offset position in the' loop 56,.as indicated by dottedy lines 60 ofFig. '4.` A similar lateral displacement will occur .when the bracket45is carried around the upper sprockets 28 and 29. .This lateraldisalignment is due tothe fact that the diagonal portions 61 of the uper :fand lower bracket 'arms 46 and 47 have a length which is greaterthanv half the distance betweenthe vvertical yportions 42 and 43 ofthechainloops. l The inward extension of the bracket 45 isthe altitude of atriangle formed by the bracket bars 46 and .47 and the ortion of chainextending between the bri ges 48 and 50 thereof, whereas the bracketbars 46 and 47 represent the sloping legs of such triangle.

For the purpose of producing movement vof the continuous traveling loopmembers formed'by the chains 40 and 41, I place a drive shaft 63parallel to the lower shafts 34 and 35, and from sprockets 64 keyed nearthe ends of the drive shaft 63 I extend chains 65 over larger s rockets66 which are keyed on the outer ends of the shafts 34 and 35. On one endof the shaft 63, such as the leftwardly projecting end 67 thereof, adrive pulley or sheave 68 of relatively large diameter is mounted. Thesprockets 64 are of the same size, as also are-the sprockets 66, thisresulting ina synchronous rotation of 85 the shafts 34 and 35 and theinner s rockets 36 and 37 when power is applied to t e drive shaft 63through a rope or belt carried from a power source and over the pulleyor sheave 68. l o At the upper end of the frame 11 I mount g cablesheaves 70 on a shaft 71 which extends between brackets 72. Over thesesheaves 70 cables7 3 are carried from hooks 74, attached to the upperends of the members 54, to a g5 counterweight which slides in a guidemember 76. The counterweight 75 is of sulficient weight to substantiallycounterbalance` the weight of the moving parts of the pumping equlpment,thus reducing to a minimum the power that must be transmitted through fthe chains 40 and 41.

To hold the sucker' rods in substantially vertical alignment during thetime the roller i 55 is offset at the lower end of a pumping 105 stroke,I provide guide rollers 78, as indicated in dotted lines in Figs. 2 and4 and as shown@ in'full lines in Fig. 1, these rollers being mounted atthe upper end' of an A-sha ed`A supportingframe 79 which may be readlly110 secured to the base 14 of the pumping equipment. The chain loops v40and 41, as may be readily perceived from Figs. 1 and 2 are, centralizedon aA single vertical plane which extends through the axes of the upperand 1'15 lower sprockets, but these 'chain loops are also situated inseparate vertical planes extending parallel to o ne another, with'theresult that the horizontal distance between the chains 40 and 41 is thesame at every point.

In Figs. 1 to 4 of the drawings I4 have shown a meanswfor compensatingfor the'disalignment of the extended end of thel bracket 45 at the endof a stroke, this compensating means including a member 57 secured tothe 126 upper extremity of the polish rod 20. In Fig. 5 I show-acompensating device which Ama be placed in any desired position on apolish rod so that the reciprocating mechavnism may be ready adjustedwith respect to A1210 the length of the sucker rods, polish rod,'and thelength of stroke of the pump. This com- 1,)ensatingmeans also provides aguide for the sucker rods to prevent disaligninent thereof when thereciprocating device is at the upper end of a power stroke. Accordingly,in Fig. 5 I show a polish rod 8O projecting through a clamp device 8l s0that the upper end 82 thereof extends a distance above the device 81..The clamp 81 consists of a pair of cooperating parts 83 and 84 whichare clamped' on the polish rod 8O by means of bolts 85. In the parts 83and 84 loops 86 and 87v are formed, these loops being horizontallyflattened and equally spaced on opposite sides of the center line of thepolish rod 80 so as to receive rollers 88 and 89 which are carried by across plate 90 by means of bearing members or pins 91. The center of thecross plate 90 is pivotally attached at 92 to the inwardly extending endof a bracket 93 carried by a chain 94, the parts 93 and 94 beingrespectively similar to the parts and 40 shown in the preceding liguresof the drawings. A guide tube or pipe 95 may extend from the clampmember 81 in vertically upward direction and in position surrounding theupper projecting end 82 of the polish rd 80. rAs shown to small scale at96 in Fig. 5, the guide tube 95 extends between guide rollers 97 and isengaged by a hook 98 situated on the end of a cable 99 which extends toa counterweight 100. The clamp device 57 shown vin Figs. l to 4 can beemployed only on the upper end of a polish rod, such as indicated at 20,but a clamp of the character shown at 81 in Fig. 5 may be situated atany desired intermediate point of adjustment on a polish rod 80, therebymaking it possible to readily adjust the long stroke reciprocatingmechanism or pumping device relative to the sucker rod system of a pumpso as to produce greatest efficiencyl in the operation of such pumpingmechanism.

Although I have herein shown and described a simple and practicalembodiment of my invention, itnis recognized that certain parts orelements thereof are representative of other parts, elements, ormechanisms which may be employed in substantially the same way toaccomplish substantially the same results; therefore, it is to beunderstood that the invention is not to be limited to the detailsdisclosed herein but shall have the scope set forth in the followingclaim.

I claim as my invention:

A device of the character described, in

cluding: a pair of 4chain loops; an upper sprocket and a lower sprocketfor each of said chain loops, said sprockets being so placed that saidchain loops will travel through parallel vertical planes; means forcausin travel of said chain loops over said sproc ets; a bracketextending inwardly from adjacent portions of said chains, the inwardextension of said bracket being substantially one-half

